THE WORK OF THE OCEAN. 



349 



the land is advancing in the face of the waves. The low coast of the 

 Middle Netherlands has retreated two miles or more in historic times/ 

 but the opposite tendency is shown at other points in the same region. 

 On the coast of England the sites of villages have disappeared by the 

 advance of the sea within historic times/ but the coast of the same 

 island affords illustrations of land advance. On the south side of Nan- 

 tucket island, the sea-cliff has been known to retreat before the waves as 

 much as six feet in a single year.^ Almost every considerable stretch 

 of coast affords illustrations both of the advance of the sea on the land 

 and of land on the sea; but in the long run, the former must exceed 

 the latter, diastrophic movements aside. 



Topographic Features Developed hy Wave-erosion, 



The sea-cliff. — The action of the waves, cutting as they do along a 

 definite horizontal zone, has been compared to the action of a horizontal 

 saw. As the waves cut into the shore at and near the water-level, the 



Fig. 308. — Standing Rock. A wave-erosion monument. West shore of Random 

 Sound, south of Clarenville, N. F. (Walcott, U. S. Geol. Surv.) 



material above, being unsupported, falls, leaving a steep face above 

 the line of cutting. This steep face is known as the sea-cliff (Figs. 301 

 to 306). The same term is sometimes applied to the chffs of lakes. 



^ Davis. Physical Geography, p. 354. 



^ Dana. Manual of Geology, 4th ed., p. 219. 



^ Shaler. Sea and Land, p. 29. 



